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Old 03-08-10, 09:10 AM   #1
DCwom
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2% grade, brakes and the GAP trail from Frostburg to Cumberland

I have a very specific question about brakes and the GAP tail. I've been investigating a ride on the Great Allegheny Passage, which is a rail-trail and I see that there is a "Max 2%" grade on the trail with the greatest change occurring from around Frostburg MD, to Cumberland, MD (~2000 ft/17 miles).

Since we have little experience with big hills and grades, can anyone comment on this section of the GAP trail with a tandem? We've never been on a rail-trail where we didn't have to pedal, and I'm guessing that the GAP is no different, but what do I know, our NJ rail-trails are pretty flat. Since we don't have a drum brake I'd be concerned if I had to drag my rim brakes for 17 miles.
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Old 03-08-10, 09:22 AM   #2
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2% is nothing to be concerned about. Light to moderate braking will easily keep your speed in check.
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Old 03-08-10, 09:34 AM   #3
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2 % grade is barely perceptible in a car, but does not escape notice by the cyclist riding it. You might or might not engage the brakes as you descend, but you will not certainly not need a drum brake.
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Old 03-08-10, 10:36 AM   #4
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To put it in perspective, if it is a rail trail, railroad cars went over it. Setting aside specialized trains (such as used in logging operations) the grade can't be that steep if they ran trains over it.

2% grade means you lose 105 vertical feet, in 5280 feet traveled. If you graphed that out, it would look almost flat.

There are lots of steeper roads in Florida, that most people would think are "flat"
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Old 03-08-10, 11:04 AM   #5
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Do not wory about brakes on a 2% incline. My guess ia that if you quit pedaling the bike would come to a slow stop...
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Old 03-08-10, 11:10 AM   #6
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I've ridden the GAP and C&O and I can't recall a need for brakes at all except to stop at the road crossings. The grade going up is slightly noticeable....but only slightly. The down grades are less so. You are always on a softer surface than blacktop or concrete so you do roll a little less effectively...don't give brakes there a second thought...enjoy the ride.

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Old 03-08-10, 11:12 AM   #7
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Suprisingly, Kruezotter predicts that a tandem with a 35olb team will roll at 29mph down a 2% grade coasting. http://www.noping.net/english/

I was surprised it was that high. I think that assumes both riders in the drops, but it still seems a bit high.

I didn't take the road surface into account, which would definitely slow it down. Also the 2% grade is the maximum grade
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Old 03-08-10, 11:57 AM   #8
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Quote:
Originally Posted by merlinextraligh View Post
Suprisingly, Kruezotter predicts that a tandem with a 35olb team will roll at 29mph down a 2% grade coasting. http://www.noping.net/english/

I was surprised it was that high. I think that assumes both riders in the drops, but it still seems a bit high.

I didn't take the road surface into account, which would definitely slow it down. Also the 2% grade is the maximum grade

Wow that is an interesting speed....certainly the surface, weight, distance and aero would be big factors.

I'm certainly not challenging Kruezotter that's for sure, but on the GAP we could not coast anywhere remotely close to that speed even if our lives depended on it....
Now, for the sake of full disclosure, I was on a cross bike not a Tandem, and the total weight including rider, bike, bags and extra water was about 230 pounds ...now that is quite a ways from a 350 pound tandem package but still!! If my fading memory can be trusted we never ever coasted at more that 15-20 mph even when we had the wind helping.
Regardless... it is a great ride and certainly worth doing.

Bill J.
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Old 03-08-10, 12:01 PM   #9
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Unless speeds of 15 - 20 mph scare you, then you will have no issues. We came down the "big glide" (from the continental divide to Cumberland) on the GAP last fall on our fully loaded tandem. Without pedaling our speed never rose above 18 - 20 mph. Keep in mind the trail is crushed limestone which slows things somewhat. We also had a little bit of a head wind. Even with a tail wind I doubt you would go much above 25 mph. A few taps on the rim brakes would easily keep your speed in control. Now, if you plan to get off the GAP on side roads the story changes. Very hilly area. A drum brake would come in handy.
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Old 03-08-10, 12:43 PM   #10
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Wish our big grades were only 2%!!!
Nothing to worry about as far as braking goes.
Crushed limestone, on the other hand, is usually OK if it is packed down.
Rode crushed limestone 3 decades ago in Wisconsin . . . we got off the trail ASAP as we suffered 2 flats in quick succession. The stone seemed to have been put down just recently and was not packed at all. Rode the road instead.
Rail trails usually have no real hills, just gentle slopes, if any.
Quit fretting and enjoy the ride TWOgether!
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Old 03-09-10, 02:24 AM   #11
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2% gradient is NOTHING, you're current brakes will be way more than sufficient.

Does anyone else find that rail trails are harder to ride that similar roads? Not only does the loose surface feel energy-sapping, but the lack of change in the gradient really gets to me - my legs seem to get more tired by having to put a constant amount of power in at a constant pedalling rate in the same gear for so long. Roads tend to undulate a bit more, and a little variety in cadence and power seems to reduce fatigue in my legs.

Rail trails are still fun, though, and it's great to get away from the cars, I've just learnt that they are far from being the most efficient or least tiring choice of route.
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